Compression fittings are widely used in a variety of instrumentation, pneumatic, hydraulic, process, power, refrigeration, industrial, mobile, transportation, aerospace, military, commercial, and other fluid power or control applications utilizing plastic or metal tubing. Compression fittings have been adapted for use with many different tubing types including metals such as copper, brass, steel, stainless steel, titanium, aluminum, and alloys such as nickel-copper, Hastelloy, Alloy 600, 6Mo, Inconel, Incoloy, and the like, and many plastics. “Lockwireless” fittings, i.e., anti-rotation fittings which do not employ a lockwire, would be well-received for commercial and military aerospace use, as well as for other applications.